Introduction[edit | edit source]
Respiratory rate (RR) is a non–invasive and useful assessment tool and abnormalities in respiratory rate have been shown to indicate patient deterioration and should be managed accordingly.
Respiration is a vital process for humans, supplying oxygen to the mitochondria for ATP production (our bodies energy currency). The main byproduct of this process, carbon dioxide which goes through a process to finally be exhaled form our lungs.
The respiratory rate, i.e., the number of breaths per minute, is highly regulated to enable cells to produce the optimum amount of energy at any given occasion.
- Our nervous system regulates the rate of oxygen inflow and carbon dioxide outflow. It adjusts it accordingly in conditions that tend to derange partial gas pressures in blood.
- Respiration is a process involving the brain, brainstem, respiratory muscles, lungs, airways, and blood vessels. All these structures have involvement structurally, functionally, and regulatory to respiration.
- Recording a full set of vital signs (pulse rate, blood pressure, respiratory rate and temperature) at least daily is considered standard for monitoring patients on acute hospital wards.
Image 1: Animation of a diaphragm exhaling and inhaling
Norms - Respiratory Rates[edit | edit source]
RR is measured by counting the number of breaths a person takes in a one-minute period. The rate should be measured at rest, not after someone has been up and walking about.
- Newborn: 30-60 breaths per minute
- Infant (1 to 12 months): 30-60 breaths per minute
- Toddler (1-2 years): 24-40 breaths per minute
- Preschooler (3-5 years): 22-34 breaths per minute
- School-age child (6-12 years): 18-30 breaths per minute
- Adolescent (13-17 years): 12-16 breaths per minute
- The average respiratory rate in a healthy adult is between 12 and 18 breaths per minute.
- Normal respiratory rates in elderly people tend to be higher than those of younger adults, especially among older adults who are in long-term care facilities
Recent evidence suggests that an adult with a respiratory rate of over 20 breaths/minute is probably unwell, and an adult with a respiratory rate of over 24 breaths/minute is likely to be critically ill.
Best Practice Procedure[edit | edit source]
Points to remember:
- Take into consideration the importance of how the person is breathing, as well as the rate at which they are breathing
- Respiratory rate, depth and symmetry are indicative of different types of conditions. eg Pneumothorax: Asymmetrical chest expansion, use of accessory muscles; Exacerbation of asthma: Dyspnoea, difficulty breathing, wheeze, tachypnoea (RR above 20 breaths per minute); Exacerbation of chronic obstructive pulmonary disease: Dyspnoea, wheeze, tachypnoea (RR above 20 breaths per minute)
- The ideal length of time to take a respiratory rate measurement is 60 seconds, without patient awareness that they are being monitored.
- Oxygen saturation measurement (eg oximetry) is not a replacement for respiratory rate measurement
- Accurate documentation and interpretation of accurately taken observations help improve patient outcomes
Importance[edit | edit source]
Changes and anomalies in RR are not simply associated with respiratory conditions, they are a good indicator that a patient is struggling to maintain homeostasis. Respiratory rate is an early, extremely good indicator of physiological conditions such as hypoxia (low levels of oxygen in the cells), hypercapnia (high levels of carbon dioxide in the bloodstream), metabolic and respiratory acidosis. Conditions in altered RR include:
- Metabolic acidosis states increase the tidal volume
- Metabolic alkalosis decreases the RR.
- Interstitial diseases that change the mechanical input to the respiratory centre lead to a rapid breathing rate.
- Congestive heart failure activates a neural circuit leading to stimulation of the respiratory centre resulting in an increase in breathing rate.
- Higher cortical centres can be affected by an increase in intracranial pressure, e.g., in a patient with head trauma or by pain in a patient with a rib fracture, resulting in an increased respiratory rate.
- The opposite effect on higher centres will be observable in an individual who has taken CNS depressant substances.
- Dehydration: Dehydration alone can result in a rapid rate of breathing.
- Fever: An increased rate of breathing with a fever is the body's attempt to lose heat by breathing faster. This is important both because a rapid respiratory rate can be a sign of a worsening infection, and because a fever needs to be taken into account in interpreting the respiratory rate.
- Hyperventilation: People may breathe more rapidly in response to stress, pain, anger or during a panic attack.
Image 2: Researchers at University College London have developed new algorithms that make it possible to use low-cost thermal cameras attached to mobile phones to track how fast a person is breathing. This type of mobile thermal imaging could be used for monitoring breathing problems in elderly people living alone, people suspected of having sleep apnea or babies at risk for sudden infant death syndrome (SIDS).
Terminology[edit | edit source]
Terms to describe abnormal respiratory rate include:
- Bradypnea is the medical term used to define breathing that is abnormally slow.
- Tachypnea is the medical term used to define an elevated respiratory rate. This rapid respiratory rate is usually shallow, versus hyperpnea which can be rapid and deep.
- Dyspnea refers to the sensation of shortness of breath and can occur with an elevated, a normal, or a decreased respiratory rate.
- Hyperpnea refers to breathing that is abnormally deep and appears laboured. It may occur with or without rapid breathing.
- Apnea means literally “no breath” and refers to the absence of breathing. eg sleep apnea
References[edit | edit source]
- Rolfe S. The importance of respiratory rate monitoring. British Journal of Nursing. 2019 Apr 25;28(8):504-8. Available: https://www.magonlinelibrary.com/doi/full/10.12968/bjon.2019.28.8.504?rfr_dat=cr_pub++0pubmed&url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org(Accessed 9.12.2021)
- Chourpiliadis C, Bhardwaj A. Physiology, Respiratory Rate.Available: (accessed 9.12.2021)
- Cretikos MA, Bellomo R, Hillman K, Chen J, Finfer S, Flabouris A. Respiratory rate: the neglected vital sign. Medical Journal of Australia. 2008 Jun;188(11):657-9.Available:https://www.mja.com.au/journal/2008/188/11/respiratory-rate-neglected-vital-sign (accessed 9.12.2021)
- Very well health What Is a Normal Respiratory Rate? Available: https://www.verywellhealth.com/what-is-a-normal-respiratory-rate-2248932(accessed 9.12.2021)